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I'm a primary organizer for the Tesla Owners Club of Orange County and we have an event on August 18 in Torrance (we do stuff North County, South County, and out of county)... (For those perusing and out of the area, here is a link to all the OFFICIAL Tesla Owners Clubs - https://www.tesla.com/support/tesla-owners-club-directory)

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If anyone is from the Inland Empire feel free to stop by we have a handful of Teslas S 3 X showing up
I'm also free to attend an OC event since I'm always in the area with friends and for food adventures.

I don't think I can make it to tomorrow's event. I already signed up for the Sunday event in Riverside tho. Are you also planning to attend that event as well? I see you have a performance white on white. Would love to sit in a performance model and see how fast it goes!

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Hey, if anyone at your club happens to have an AWD, and someone else happens to have a RWD in a matching wheel config (preferably with similar tread wear)... could you ask if they could be bothered to drive out to somewhere flat (ideally a couple miles long) at a time when there's no traffic and record their energy consumption driving the same route, forwards and backwards, same tire pressure, same payload weight, close enough together so as weather conditions are the same (but far enough apart so as not to draft), at round-trip speeds of 55, 65, 75, and 85 mph?

Some of us have been trying to get our hands on data like that for ages, but no luck

Top-Contributor

Hey, if anyone at your club happens to have an AWD, and someone else happens to have a RWD in a matching wheel config (preferably with similar tread wear)... could you ask if they could be bothered to drive out to somewhere flat (ideally a couple miles long) at a time when there's no traffic and record their energy consumption driving the same route, forwards and backwards, same tire pressure, same payload weight, close enough together so as weather conditions are the same (but far enough apart so as not to draft), at round-trip speeds of 55, 65, 75, and 85 mph?

Some of us have been trying to get our hands on data like that for ages, but no luck

Active Member

Hey, if anyone at your club happens to have an AWD, and someone else happens to have a RWD in a matching wheel config (preferably with similar tread wear)... could you ask if they could be bothered to drive out to somewhere flat (ideally a couple miles long) at a time when there's no traffic and record their energy consumption driving the same route, forwards and backwards, same tire pressure, same payload weight, close enough together so as weather conditions are the same (but far enough apart so as not to draft), at round-trip speeds of 55, 65, 75, and 85 mph?

Some of us have been trying to get our hands on data like that for ages, but no luck

Honestly - this just seems like entirely too many variables which would need to be controlled. The only way your going to get more accurate is to hack into the diagnostics mode to get more accurate data. Without that, this "test" would require a significant distance to be traveled. You would then have to factor in driving styles (someone better or worse at regen braking). This isn't even factoring in many other variables in play - for example - heating & cooling of the batteries. I also believe a performance model is physically different in it's drive train than a dual motor. So that model would not be a good comparison.

Rather than trying to propose your solution, explain in detail what problem your trying to solve and start a new thread.

Not really. Weight's the same. Tires are the same, so long as tread wear is similar. Battery temperature (not really key for efficiency unless you're outside the acceptable thermal bounds - that's more of a power thing) would be quite similar if the distances driven to get there were either A) similar, or B) long. Speed would be identical - cruise control locked. Payloads similar enough to within the margin of error. Weather identical, within the variability of a few minutes spacing. Terrain would be identical. Pretty darn controlled. A couple miles is more than enough measurement data. No need to "hack into the diagnostics mode".

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The whole point is the energy consumption difference between AWD and RWD on an otherwise identical config. That video doesn't have anything to do with AWD vs. RWD.

The EPA testing left a giant question hanging. The weight difference between AWD and RWD should cause no more than a 3%-ish efficiency difference, yet the ratings are over 10% different. There are three main theories as to what's going on, and we really don't know which is correct.

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A) Tesla says that torque sleep is active, but it could be broken or a poor implementation. This would leave the vehicle overusing its (inefficient) front motor when it should be fully slept (induction machines fully freewheel when there's no armature current).

B) The EPA testing could have been done with a different (less efficient) wheel/tire config than the RWD, since the testing is supposed to be based around configurations that will be commonly purchased by buyers for the model tested.

C) There could be an unexpectedly huge amount of frictional drivetrain losses on the front axle.
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In the case of theory (B), the two vehicles should come quite close to each other in terms of energy consumption - 3% ish. In the case of theories (A) and (C), there should be a significant difference between the two - 10%-ish. The distinction between (A) and (C) could be determined with a rolldown test; if (A) were true, then both AWD and RWD would have similar rolldowns. If (C) were true, AWD would rolldown faster.

Which theory is correct has big implications for buyers. If (A) is correct, there's nothing you can do about it if you get AWD, but it'll probably get fixed in an update in the first year or two, giving you a ~20+ mile range boost. If (B) is correct, the problem is fully avoidable just by wheel config choice. If (C) is correct, tough luck - you're stuck with the bad efficiency if you want AWD.

Active Member

Not really. Weight's the same. Tires are the same, so long as tread wear is similar. Battery temperature (not really key for efficiency unless you're outside the acceptable thermal bounds - that's more of a power thing) would be quite similar if the distances driven to get there were either A) similar, or B) long. Speed would be identical - cruise control locked. Payloads similar enough to within the margin of error. Weather identical, within the variability of a few minutes spacing. Terrain would be identical. Pretty darn controlled. A couple miles is more than enough measurement data. No need to "hack into the diagnostics mode".

Actually - weight is not the same in a RWD vs AWD. You would have to account for the front motor and any extra equipment that might be needed (cables, etc).

While it maybe a rumor - I understood the information given to the EPA was to even out the range across all models within Long Range batteries (RWD, AWD, Performance). So I'm sure RWD will have longer range.